package com.example.tools;


import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;


public class DBUtils
{
    final static String URL="jdbc:mysql://localhost:3306/crm";
    final static String USERNAME="root";
    final static String PASSWORD="abc123456";

    static
    {
        // 加载驱动
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            System.out.println("没有找到驱动,检查是否有添加mysql驱动jar包");
        }
    }

    /**
     * 获取连接
     * @return 返回一个连接
     * @throws SQLException
     */
    public static Connection getConnection() throws SQLException
    {
        Connection conn = DriverManager.getConnection(URL,USERNAME,PASSWORD);
        return conn;
    }

    /**
     * 释放资源
     * @param conn
     * @param stmt
     * @param rs
     */
    public static void destoryResource(Connection conn,Statement stmt,ResultSet rs)
    {
        if(rs!=null)
        {
            try {
                rs.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        if(stmt!=null)
        {
            try {
                stmt.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        if(conn!=null)
        {
            try {
                conn.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

}
